OBJECT        = COLUMN
   NAME           = MET
   COLUMN_NUMBER  = 1
   BYTES          = 4
   DATA_TYPE      = MSB_UNSIGNED_INTEGER
   START_BYTE     = 1
   DESCRIPTION = "Mission elapsed time, in seconds, corresponding to the 
   start of the accumulation period for the spectra."
END_OBJECT            = COLUMN  

OBJECT        = COLUMN
   NAME           = ACCUM_TIME
   COLUMN_NUMBER  = 2
   BYTES          = 4
   DATA_TYPE      = MSB_UNSIGNED_INTEGER
   START_BYTE     = 5
   DESCRIPTION = "Accumulation time, in seconds, of the anti-coincidence
   shield detector."
END_OBJECT    = COLUMN

OBJECT        = COLUMN
   NAME           = MIDPOINT_MET
   COLUMN_NUMBER  = 3
   BYTES          = 4
   DATA_TYPE      = MSB_UNSIGNED_INTEGER
   START_BYTE     = 9
   DESCRIPTION = "The mission elapsed time at the midpoint of the
   observation. Defined as:
   MET at the start of the observation +  (ACCUM_TIME / 2)."
END_OBJECT    = COLUMN

OBJECT        = COLUMN
   NAME           = ORBIT_NUMBER
   COLUMN_NUMBER  = 4
   BYTES          = 2
   DATA_TYPE      = MSB_UNSIGNED_INTEGER
   START_BYTE     = 13
   DESCRIPTION    = "Orbit number is a unique identifier for a given orbit of
   the MESSENGER spacecraft around Mercury. Orbit number is defined as
   starting at apoherm and is calculated using the MET value and the
   appropriate SPICE kernels. Orbit numbering does not start until MESSENGER
   performs the Mercury orbit insertion. Until that time the value for orbit
   number is 0."
END_OBJECT    = COLUMN

OBJECT        = COLUMN
   NAME           = START_BIN
   COLUMN_NUMBER  = 5
   BYTES          = 2
   DATA_TYPE      = MSB_UNSIGNED_INTEGER
   START_BYTE     = 15
   DESCRIPTION = "The bin containing first shield counter (starting from 
   zero). Nominally is zero."
END_OBJECT    = COLUMN

OBJECT        = COLUMN
   NAME           = NUMBER_OF_BINS
   COLUMN_NUMBER  = 6
   BYTES          = 2
   DATA_TYPE      = MSB_UNSIGNED_INTEGER
   START_BYTE     = 17
   DESCRIPTION = "Number of bins in each science packet."
END_OBJECT    = COLUMN

OBJECT        = COLUMN
   NAME           = GRS_PRIORITY_LEVEL
   COLUMN_NUMBER  = 7
   BYTES          = 2
   DATA_TYPE      = MSB_UNSIGNED_INTEGER
   START_BYTE     = 19
   DESCRIPTION = "Indicates the type of priority assigned to the science
   packet. The priority level is tied to the ApID of the packet. Priority
   level varies from 0-3, 0 being highest and 3 being lowest priority."
END_OBJECT    = COLUMN

OBJECT        = COLUMN
   NAME           = MISSING_DATA_PACKETS
   COLUMN_NUMBER  = 8
   BYTES          = 2
   DATA_TYPE      = MSB_UNSIGNED_INTEGER
   START_BYTE     = 21
   DESCRIPTION = "The value represents a 16-bit binary number where each bit
   indicates whether a shield count rate telemetry packet is missing from 
   the EDR. Each GRS_SCR EDR consists of information extracted from 16 
   telemetry packets in a complete observation. The least significant bit is 
   a flag corresponding to the first of 16 packets and the most significant 
   bit is a flag corresponding to the 16th packet. A bit value of 1 
   indicates that a given packet is missing from the EDR. 
   For example, a value of 0 in this column indicates that the spectra from 
   all 16 packets have been downloaded and included in the count rate spectra 
   for this EDR. A value of 3 indicates that the count rate information from
   the first and second packets are missing and therefore channels 0-2047 
   should be discounted from analysis of the GRS_SCR spectra. A value of 
   three or greater would indicate the EDR contains no valid data, since the 
   count rates are only contained in the first 2000 channels."
END_OBJECT    = COLUMN

OBJECT        = COLUMN
   NAME           = BAD_DATA_FLAG
   COLUMN_NUMBER  = 9
   BYTES          = 2
   DATA_TYPE      = MSB_UNSIGNED_INTEGER
   START_BYTE     = 23
   DESCRIPTION = "Intended for use as a bit-string bad data flag to indicate
   specific problems associated with the data. Values are expected to be 
   assigned to specific bits as problems are identified during the course of
   the mission. Currently no values have been assigned and will default to a
   value of zero."
END_OBJECT    = COLUMN

OBJECT        = COLUMN
   NAME           = SHIELD_COUNT_SPECTRA
   COLUMN_NUMBER  = 10
   BYTES          = 32768
   DATA_TYPE      = MSB_UNSIGNED_INTEGER
   START_BYTE     = 25
   ITEMS          = 16384
   ITEM_BYTES     = 2
   DESCRIPTION = "High-time-resolution counter of the total event rate in 
   the shield detector. Counter operates at a 10-ms cadence for the duration 
   of the accumulation period, resulting in a series of measurements that 
   populate the 16384 channel spectra. When fewer than 16384 channels are 
   required, the remainder are set to zero. When more than 16384 channels 
   are required, the last channel represents the sum of all measurements 
   made after the array is filled. For all cases, the first approximately 
   fifty channels are zero due to signal processing deadtime in the GRS 
   electronics. The use of a 16384-channel array is the result of a flight 
   software change to retask a defunct GRS packet into a shield rate counter 
   without changing the format of the packet itself."
END_OBJECT      = COLUMN